"The stake crimp is specified on .303 British military ammo..."
That's more than a standard 3-stab stake crimp....
Jean Huon's book also shows examples that appear to have a rather heavy neck crimp instead of a stake crimp.
Ah. Here we go.
Fourth picture down on this page shows a number of WW II era British-made .303 cartridges with a heavy neck crimp.
Those photos are also a pretty good indication of what kind of variations you'd see in the case neck.